nd 1894 it was fully recognised that a
regular course of change occurred dependent upon the succession of the
seasons, as had been first suggested by Schiaparelli. As the polar snows
melt the adjacent seas appear to overflow and spread out as far as the
tropics, and are often seen to assume a distinctly green colour. These
remarkable changes and the extraordinary phenomena of perfect straight
lines crossing each other over a large portion of the planet's surface,
with the circular spots at their intersections, had such an appearance
of artificiality that the idea that they were really 'canals' made by
intelligent beings for purposes of irrigation, was first hinted at, and
then adopted as the only intelligible explanation, by Mr. Lowell and a
few other persons. This at once seized upon the public imagination and
was spread by the newspapers and magazines over the whole civilised
world.

_Existence of Seas doubted._

At this time (1894) it began to be doubted whether there were any seas
at all on Mars. Professor Pickering thought they were far more limited
in size than had been supposed, and even might not exist as true seas.
Professor Barnard, with the Lick thirty-six inch telescope, discerned an
astonishing wealth of detail on the surface of Mars, so intricate,
minute, and abundant, that it baffled all attempts to delineate it; and
these peculiarities were seen upon the supposed seas as well as on the
land-surfaces. In fact, under the best conditions these 'seas' lost all
trace of uniformity, their appearance being that of a mountainous
country, broken by ridges, rifts, and canyons, seen from a great
elevation. As we shall see later on these doubts soon became
certainties, and it is now almost universally admitted that Mars
possesses no permanent bodies of water.

CHAPTER II.

MR. PERCIVAL LOWELL'S DISCOVERIES AND THEORIES.

_The Observatory in Arizona._

In 1894, after a careful search for the best atmospheric conditions, Mr.
Lowell established his observatory near the town of Flagstaff in
Arizona, in a very dry and uniform climate, and at an elevation of 7300
feet above the sea. He then possessed a fine equatorial telescope of 18
inches aperture and 26 feet focal length, besides two smaller ones, all
of the best quality. To these he added in 1896 a telescope with 24 inch
object glass, the last work of the celebrated firm of Alvan Clark &
Sons, with which he has made his later discoveries. He thus became